The present invention relates to a solder component, particularly to a solder component to be subjected to surface-mount process on a substrate.
Surface-mount technology has been conventionally employed as a method for mounting a solder component such as an electronic component or a semiconductor component on a substrate. Surface-mount technology is a method for fixing a solder component to a substrate by disposing the solder component on the substrate surface on which a solder paste has been coated, and subsequently heating the substrate in a high-temperature furnace to melt the solder.
An example of a solder component to be mounted through the surface-mount technology is disclosed in JP2013-254797. The solder component includes a plurality of lead portions 2 drawn from a component body 1, each of the lead portions 2 has a planar portion 3 opposing a substrate that is not shown, and the planar portion 3 is provided with a projection 4 projecting toward the substrate, as illustrated in FIG. 11.
For instance, as illustrated in FIG. 12, eight lead portions 2 can be provided, and the projections 4 are arranged such that the center of mass G of the solder component is located inside a quadrilateral S1 determined by the projections 4 of the eight lead portions 2, whereby the solder component that is disposed on the substrate surface attempts to have stable attitude.
However, even though as many as eight lead portions 2 are provided, in reality, the solder component disposed on the substrate surface is supported by only the projections 4 of any three lead portions 2 surrounding the center of mass G.
In addition, since every lead portion 2 is provided with the projection 4 on the planar portion 3 thereof, variation in shape of the projections occurring in production, e.g., generation of burrs on the projections 4, decides which projections 4 of the lead portions 2 out of the projections 4 of the eight lead portions 2 come into contact with the substrate surface when the solder component is disposed on the substrate surface; it is impossible to specify which three projections 4 of the lead portions 2 would support the solder component in reality, even if every solder component is produced in the identical design.
Therefore, when the solder component is supported by three projections 4A as illustrated in FIG. 12, for example, a triangle S2 is determined by the three projections 4A which are linked to one another, and the center of mass G of the solder component is located on a hypotenuse 5 of the triangle S2. Accordingly, the solder component would become so unstable that, if the solder component receives even a small external force when being soldered, the attitude of the solder component would change and possibly cause connection failure.